摘要：
Objective To evaluate the antibacterial activity of novel amino acid-porphyrin photosensitizer against 11 kinds of clinical isolated sensitive and multi-resistance strains, and to test its cytotoxicity to HaCaT and RAW264.7 cells, in order to provide basis for in vivo experiment.Methods Two-fold dilution method was used to co-culture different concentration photosensitizers with bacterial suspension for 30 min in the dark, and the culture mix were immediately irradiated by red laser (650 nm, 6 J/cm2) for 30 min.After irradiation, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 4I to different strains were evaluated using tablet coated plate method, the MIC50 and MIC90 values were calculated, and the cytotoxicity of 4I to HaCaT and RAW264.7 cells were determined by CCK-8 assay.Results The results showed that, except Proteus mirabilis and Morganella strains, 4I was efficient to all of the rest strains, and there was no variability of the effectiveness between sensitive and multi-resistance strains.The MIC50 and MIC90 values were 0.822 μmol/L and 1.947 μmol/L, respectively.Photosensitizer or irradiated by red laser alone showed mild promotion on HaCaT cells growth (P＜0.05), while no effect was observed on RAW264.7 cells.After photodynamic therapy, survival rates of HaCaT and RAW264.7 cells under 4I concentration of 0.98 μmol/L were (92.24±13.64)％ and (103.84±1.59)％, respectively.IC50 values were 1.846 μmol/L and 7.447 μmol/L, which suggested low-cytotoxicity effect under efficient inhibitory bacterial concentration.Conclusions The novel amino acid-porphyrin photosensitizer 4I has high efficiency and broad spectrum antimicrobial properties, no cytotoxicity, and low toxic side effect.It has promoting effect on cell growth, and is a promising antimicrobial photosensitizer.The antimicrobial therapy of photosensitizer with lower power red laser has more broad application prospect.%目的 评价新型氨基酸卟啉光敏剂4I对临床分离的敏感菌株和多重耐药菌株的抗菌活性;分别检测其对人永生化表皮细胞HaCaT及单核巨噬细胞RAW264.7的细胞毒性,为体内实验提供基础.方法 用二倍稀释法将不同浓度的光敏剂与菌悬液避光孵育30 min后,立即行红色弱激光照射30 min(650 nm,6 J/em2),采用涂板计数法评定41对不同菌株的最小抑菌浓度(MIC)和最小杀菌浓度(MBC),并计算MIC50和MIC90;CCK-8法分别检测4I对HaCaT及RAW264.7细胞的细胞毒性.结果 除奇异变形杆菌和摩根摩根菌外,4I对其余菌株均有效;灭活同一菌种的敏感菌和耐药菌效果差异无统计学意义(P＞0.05);MIC50及MIC90分别为0.822 μmol/L和1.947μmol/L;单独光敏剂孵育及单纯红色弱激光照射30 min后,显示有促HaCaT细胞生长作用(P＜0.05),对RAW264.7细胞存活率则无影响;当4I的浓度为0.98 μmol/L时,HaCaT和RAW264.7细胞的存活率分别约为92.24％± 13.64％和103.84％±1.59％,半抑制浓度(IC50)分别为1.846 μmol/L和7.447 μmol/L,表明在有效抑菌浓度下对细胞毒副作用较弱.结论 新型氨基酸卟啉类光敏剂4I具有高效、广谱的抗菌活性,无细胞毒性,低毒副作用,且具有促细胞生长作用,是一种前景极佳的抗菌光敏剂,将其结合红色弱激光的光动力抗菌疗法具有广阔的应用前景.
